Apparatus for tapping couplings.



J. H. BAKER & D. ANDERSON; APPARATUS FOR TAPPING COUPLINGS.

APPLICATION FILED PBB.25, 1909.

Patented Jan; 25, 1 910.

May? W W 59M MW print w s ranrorrrb JONATHAN MAKER All DAVID ANDERSON,0F llVICKEEPORT, ZEENNSZ'I.JT1lt.l\TL 3t, ASSIGNORS TO NATIONAL TUBECOMPANY, OF PITTSBURG, PENNSYLVANIA, A GOR- PORATION OF NEW JERSEY.

crater.

Specification of Letters Patent.

APPARATUS FOR TAPIPING COUPLINGS..

' Application filed February 25, 1909. Serial No. M936? To all whom t'tmay concern:

Be it known that we, JONATHAN H. BAKER and DAVID Anonnson', both of MoKeesport, .tllcgheny county, Pennsylvania, have invented a riew anduseful Apparatus for Tapping Couplings, of which the following is afull, clear, and exact description, reference being bad to the accompanying drawings, forming part of this specification, in which "Figure 1 isa plan view partly in section showing improved apparatus constructed.and arranged in accordance with our invention; Fig. 2 is a sectionalside elevation taken on'the line'II-TII of Fig. 1 showing .the parts asarranged during the tapping operation: Fig. 3 is'a partial sideelevation and Fig. 41 is an end elevation of the coupling tap withthepilot removed, showing the manner in which the radially movablecuttors are secured'in place.

@ur inventioir relates to the class 0: cutting tools employed in cuttinginternal threads in pipe couplings, sockets and other pipe fittings, andalso used for tapering straight threads which have been cut in thecoupling or other fitting by a previous operation.

The object of our invention is to provide an improved apparatus forcutting and tapering the threads on such couplings by the use of whichthe successive threads are made uniform in size and which are cut to thecorrect angle 'and taper.

Another object of the invention is'to provide improved apparatus in theuse of which the threads are cut on the couplings outwardly, from apoint intermediate of the length of the couplings and by which oppositeends of the couplings can be tapped with right and left hand threads.

A further objectof our invention is to provide improved means foradjusting the tap and mandrel relatively to each other to the couplings.

j Another object of the invention is to provide apparatus in which thecutters on the taps are moved out of engagen'ient with the couplingswhen the threading operation has been completed, in this way avoidingthe necessity of backing out or unscrewing the tap from the threadedcoupling.

'Heretotore in the use of apparatus of this class, difiiculty has beenfound in cutting spindle tapping machine.

provided witha basket 3 having an adjust threads which are free frominequalities and in preventing the-angle of the successive threads fromvarying. By the use of our improved apparatus, these difiiculties areovercome, the threads are cut straight and true on the couplings and thequality of the finished couplings is greatly improved.

In the drawings-2 represents the table of a vertical tapping machinewhich is shown as one of a plurality of such tables formed integral toprovide a multiple The table 2 is ing ring 4.- therein, the ring l beingadjusted vertically by means of the adjusting screws 5. Sliding onsuitable ways or guides 6 are the clamping jaws by which the couplings 8able squared portion ld which engages with the socket in the end of therotating spindle on the tapping machine. The tap 12 is provided with aplurality of radially movable chasers or cutters 15, these cutters beingheld in place by means of the tap pilot 16 which is secured to the endof the tap 12 by means of the cap screws 17.

Beneath the table 2 is an arm '18 in which Patented Jan. 25, 191d.

the mandrel or pilot pin 19 issadjustably secured. The pilotpin onmandrel 19 is removably secured in the socket 520 which in turn issecured in a screw threaded sleeve 21 which is inserted in an opening inthe arm 18. The sleeve 21 is provided with ad justin-g nuts 22 by whichthe sleeve with the mandrel socket and mandrel are adjusted verticallyon the arm 18. 1

In the operatioh of tapping couplings with our improved apparatus, theadjusting ring in the basket 3 and the mandrel 19 mounted on the arm 18are adjusted relatively to each other so as to bring the taperedportion'23 of the mandrel into position to properly engage with theradially in a preliminary operation threads on the coupling areafterward ta- .coupling from rotation,

'vanced the cutters 15 into wardly tapering thread are then retractedand movable cutters 15 on the tap. The tap '12 is put in place on thespindles of the tapping machine and the coupling 8 is put on theadjusting ring 4. The jaws 7 are then advanced until the plates 9 gripand hold the The spindle is then caused to rotate and'the tap 12 isadvanced into the coupling. When the cutters 15 are advanced into thecoupling to about half the length of the coupling, the tapered portion23 of the mandrel 19 will have adcutting engagement with the couplings.As the tap 12 is further advanced the cutters are gradually movedradially outward so as to cut an outwhich extends from about the'middleof the length ofthe coupling to its outer edge. This completes thecutting operation for one half of the coupling and when this operationis finished the cutters 15 are clear of the not require being backed outof the coupling as is the usual case. The gripping jaws .7 the releasedcoupling is reversed in its position on the adjusting ring 4L, theclamping jaws are again tightened and the above described operation isagain re eated and the second half of the length 0 the coupling isthreaded.

In some cases it is desirable to cut right and left hand threads on thecoupling, in which case one end of the coupling will be tapped with aright or left handitap and the coupling then finished by cutting threadsof the other hand to that first out.

With some couplings the threads are firstcut straight throughout thelength of thecoupling and the straight pcred in a second operation inwhich our improved tap is used which will taper the threads in the samemanner as that described for cutting the threads.

The advantages of our invention will be coupling and do their length setour hands.

apparent to those skilled in the art. By means of our improved apparatuscouplings of different lengths and sizes may be tapped by adjusting themandrel 19 to the required position so as to engage with the radiallymovable cutters at the proper point. The couplings are tapped from thecenter of outwardly and a tapering thread is cut. The cutters do notrock during the cutting operation and a true thread having the sameangle of thread throughout is obtained.

Modifications in the construction and ar rangement of theparts may bemade without departing from our invention. Instead of applying ourinvention to a vertical tapping machine as shown, the apparatus may behorizontal. The number of taps may be varied as is desired; the numberof the radially movable cutters on the taps may be changed, and othervariations may be made in the construction of the apparatus withoutdeparting from our invention.

We claim:

Apparatus for tapping couplings comrisin a ta havin a radiall movablecut-- ter, means for holding the couplin s while being tapped and amandrel secured to said coupling-holding means for controlling theradial movement ofthe cutter in the coupling, said mandrel be'ihgarranged to hold the axis of rotation of the cutter concentric with theaxis of the coupling and having means permitting the insertionof the tapinto the coupling without engaging with the.-

coupling; substantially as described.

In testimony whereof, we have hereunto JONATHAN H. BAKER. DAVIDANDERSON. \Vitnesses JAs. P. DAVIS, Jos. T. ARMSTRONG.

